Haloperidol decanoate

FGA Depot·Psychiatry - Depot Antipsychotics

Maintenance treatment of Schizophrenia

PBSDEPOT Q4WHaldol DecanoateS4TGA

Max Dose

300 mg Q4W

Half-life

3 Weeks

EPS Risk

CRITICAL

Z-Track IM

REQUIRED

Rapid Summary

Overview

First-Generation Antipsychotic (FGA) depot. Extremely potent D2 antagonist dissolved in sesame oil. Highly effective for treatment-resistant positive symptoms but carries brutal EPS risks.

Maximum Dose

Max 300 mg every 4 weeks (Doses > 100 mg are rarely needed and highly toxic).

Clinical Focus

Because it is oil-based, it MUST be injected using the Z-Track method to prevent the oil leaking back into the subcutaneous fat and causing tissue necrosis.

Bottom Line

Haloperidol decanoate is a first-generation long-acting injectable antipsychotic for chronic schizophrenia, but causes significant extrapyramidal side effects and tardive dyskinesia with long-term use.

Formulation & Access

Brand Names

Haldol Decanoate

Parenteral

Ampoules (50 mg/1 mL, 100 mg/1 mL). Thick oil solution.

Prescribing & PBS

Unrestricted General Benefit (S4).

Indications & Use

Primary

PBSTGA

Maintenance treatment of Schizophrenia.

Clinical Place

Reserved for older patients stabilized on it for decades, or highly severe psychotic patients who fail SGAs. Almost never used as a first-line depot today.

Quick reference

Class & Role

FGA Depot — First-Generation Antipsychotic (FGA) depot.

Route / Formulation

Ampoules (50 mg/1 mL, 100 mg/1 mL). Thick oil solution. (Haldol Decanoate)

Usual Dose & Max

IM 50-100 mg every 4 weeks. Deep gluteal injection. Max 300 mg every 4 weeks (Doses > 100 mg are rarely needed and highly toxic).

Key Indication Doses

Schizophrenia: IM 50-100 mg every 4 weeks. Deep gluteal injection. Initiation: Calculate total daily oral dose, multiply by 10-15 to get the monthly depot dose. Requires PO overlap for 2-3 weeks. Elderly: Max 12.5 - 25 mg every 4 weeks. Extremely sensitive to EPS.

Best Uses

Avoid / Cautions

Parkinson's disease, severe CNS depression, sesame oil allergy. Pregnancy Category C.

Key Risks

Neurological: Severe Extrapyramidal Side Effects (Parkinsonism, acute dystonia, severe akathisia). Tardive Dyskinesia risk is very high. Neuroleptic Malignant Syndrome (NMS). Cardiovascular: QTc prolongation. Endocrine: Hyperprolactinemia.

Key Interactions

Avoid concurrent QTc prolonging drugs (e.g., Amiodarone, Macrolides). Strong CYP2D6 or CYP3A4 inhibitors significantly raise haloperidol levels.

Monitoring

Monitor for EPS (stiffness, tremor). A PRN anticholinergic (Benzatropine) should be charted when initiating. Baseline ECG (QTc check) before first injection.

Clinical Pearl

Because the carrier is sesame oil, if you inject straight in and pull the needle out, the oil will track back up the needle hole into the subcutaneous fat, causing a painful sterile abscess. You MUST pull the skin to the side (Z-Track), inject, wait 10 seconds, pull the needle out, and let the skin slide back to 'trap' the oil in the muscle.

Access

Haldol Decanoate

Brand: Haldol Decanoate

Haloperidol decanoate

FGA Depot·Psychiatry - Depot Antipsychotics

Maintenance treatment of Schizophrenia

PBSDEPOT Q4WHaldol DecanoateS4TGA

Max Dose

300 mg Q4W

Half-life

3 Weeks

EPS Risk

CRITICAL

Z-Track IM

REQUIRED

Rapid Summary

Overview

First-Generation Antipsychotic (FGA) depot. Extremely potent D2 antagonist dissolved in sesame oil. Highly effective for treatment-resistant positive symptoms but carries brutal EPS risks.

Maximum Dose

Max 300 mg every 4 weeks (Doses > 100 mg are rarely needed and highly toxic).

Clinical Focus

Because it is oil-based, it MUST be injected using the Z-Track method to prevent the oil leaking back into the subcutaneous fat and causing tissue necrosis.

Bottom Line

Formulation & Access

Brand Names

Haldol Decanoate

Parenteral

Ampoules (50 mg/1 mL, 100 mg/1 mL). Thick oil solution.

Prescribing & PBS

Unrestricted General Benefit (S4).

Indications & Use

Primary

PBSTGA

Maintenance treatment of Schizophrenia.

Clinical Place

Reserved for older patients stabilized on it for decades, or highly severe psychotic patients who fail SGAs. Almost never used as a first-line depot today.

Quick reference

Class & Role

FGA Depot — First-Generation Antipsychotic (FGA) depot.

Route / Formulation

Ampoules (50 mg/1 mL, 100 mg/1 mL). Thick oil solution. (Haldol Decanoate)

Usual Dose & Max

IM 50-100 mg every 4 weeks. Deep gluteal injection. Max 300 mg every 4 weeks (Doses > 100 mg are rarely needed and highly toxic).

Key Indication Doses

Best Uses

Avoid / Cautions

Parkinson's disease, severe CNS depression, sesame oil allergy. Pregnancy Category C.

Key Risks

Key Interactions

Avoid concurrent QTc prolonging drugs (e.g., Amiodarone, Macrolides). Strong CYP2D6 or CYP3A4 inhibitors significantly raise haloperidol levels.

Monitoring

Monitor for EPS (stiffness, tremor). A PRN anticholinergic (Benzatropine) should be charted when initiating. Baseline ECG (QTc check) before first injection.

Clinical Pearl

Access

Haldol Decanoate

Brand: Haldol Decanoate